A search through the public records of the U.S. Patent and Trademark Office disclosed the following four U.S. patent references:
U.S. Pat. No. 1,380,358 is relevant to that portion of the present invention which stabilizes the launch tube (2) along its longitudinal (roll) axis. Forward muzzle deflectors 4, outwardly diverging tubular deflector 2, and springs 27 of the reference balance recoil. Recoil is not a problem in the present invention because the launch tube (2) is open ended, not close ended.
U.S. Pat. No. 2,787,938 shows frusto-conical closure element 28 for opening a launch tube to prevent damage due to exhaust gases and to avoid recoil. Element 28 does not counteract undesired torques, as does trim tab 20 in the present invention.
U.S. Pat. No. 3,548,707 counteracts torque about the roll axis of a missile fired from a rifled gun tube launcher. Rotation about the roll axis is not a problem in the present invention, which addresses linear displacements along the roll axis and torques about the pitch axis of the launch tube (2).
U.S. Pat. No. 4,044,648 shows doors (76, 78) which act as check valves to allow multiple launch tubes to exhaust into a common plenum while preventing exhaust products from damaging unfired adjacent missiles.